Three of the major ligninolytic enzymes, lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (LA), as well as the secretome of a white-rot fungi, Grammothele fuligo, are tested on three industrial lignins (organosolv, alkali, and Kraft), to investigate and study the differences in biodegradation reactions and mechanism of these three lignins. Strategies involving additives in laccase mediated systems were also considered to produce small phenolic compounds. Three new or underreported additives including 2,4,6-tri-tert-butylphenol (TTBP), 4-tert-butyl-2,6-dimethylphenol (TBDMP), and 3hydroxyanthranilic acid (HAA) are compared to three classic laccase mediators violuric acid (VA), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 1-hydroxybenzotriazole (1-HBT). Decrease of molecular weight by up to 73% could be obtained on organosolv lignin with LA−VA systems, and by 49%, 43%, and 39% when LA was used with ABTS, TBDMP, and 1-HBT, respectively. In-depth analysis of the degradation products by quantitative 2D HMQC NMR indicated that the oxidation is mediator-dependent and provides new insights on the enzymatic mechanism.

The levoglucosenone-based norbornenes family was extended to include a new bi-functional methacrylate monomer that, upon ROMP in Cyrene™, leads to polymers with pendent methacrylate moieties which can be modified by post-polymerization reactions.

Lignin has been widely studied as a sustainable source of renewable materials, particularly aromatic feedstock chemicals, which are in great and increasing need in the world. Lignin oxidation and depolymerization presents a promising approach to functionalized phenolic products. In this work, a novel oxidative degradation of lignin using a formate ionic liquid was investigated resulting in ethyl acetate soluble and also water‐soluble depolymerized lignin products. The β‐O‐4 bonds in lignin were oxidized and then depolymerized by a recyclable ionic liquid, 2‐hydroxy ethylammonium formate. 2‐Hydroxy ethylammonium formate, which could dissolve lignin acting as a solvent, was found to also catalyze the depolymerization of the oxidized lignin. The lignin depolymerization products were characterized.

In this work, we proved the efficient synthesis of a bio-based hyper-branched polyphenol from a modified lignin degradation fragment. Protocatechuic acid was readily obtained from vanillin, a lignin degradation product, via alkaline conditions, and further polymerised to yield high molecular weight hyperbranched phenol terminated polyesters. Vanillic acid was also subjected to similar polymerisation conditions in order to compare polymerisation kinetics and differences between linear and hyperbranched polymers. Overall, protocatechuic acid was faster to polymerise and more thermostable with a degradation temperature well above linear vanillic acid polyester. Both polymers exhibited important radical scavenging activity (RSA) compared to commercial antioxidant and present tremendous potential for antioxidant applications.

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